Question

Rosemary works two part-time jobs while attending college. During the day she works at the college bookstore and earns $8.25 per hour. In the evening she delivers pizza for Papa Gino's, earning $9.25 per hour. If Rosemary earned $247 last week from working a total of 28 hours, find how many hours she worked at Papa Gino's last week.

Answer 1

Answer: 16 hours

Explanation:

We will write a system of equations to help us solve. Let x be equal to the number of hours worked at the college bookstore, and y be equal to the number of hours worked at Papa Gino's.

First, we will write an equation for the money earned. Then, we will write one for the hours worked.

8.25x + 9.25y = 247

x + y = 28

Now, we will will substitute the second equation into the first and solve for the hours worked at Papa Gino's last week, equal to y.

x + y = 28 ➜ x = -y + 28

8.25x + 9.25y = 247

8.25(-y + 28) + 9.25y = 247

-8.25y + 231 + 9.25y = 247

y + 231 = 247

y = 16

Rosemary worked 16 hours at Papa Gino's last week.